This invention relates to image processing apparatus and methods.
The invention is more particularly concerned with image processing apparatus and methods for use in determining the range and or alternatively the size of an object.
Conventional techniques of measuring the range of an object involve the use of a laser or radar rangefinder. While these can be accurate, they have the disadvantage that they must be precisely aimed and can make the presence of the observer apparent. It is common practice for tanks and military aircraft or vessels to be equipped with laser and radar detectors so that an alarm is given when they are under observation by laser or radar radiation. The detector can be used to direct counter-measures at the laser or radar source which is used to provide a homing beacon for a missile or the like.
It would, therefore, be a considerably advantage to be able to measure the range and size of an object remotely in a passive way without increasing the risk of detection.